Are flashdrives really safe from an EMP?
And btw, does a faraday cage still protects a computer if it's plugged on the wall and on the Internet (if not using fiber to get the 'net inside the cage) ?
1. no, an EMP of sufficient power would induce a current in the circuitry and trash the thing.
2. maybe. an EMP would result in a massive electrical surge. the computer would be unaffected (beyond the effects of losing power suddenly) if there is sufficient surge suppression capability between the wall and the computer.
A Faraday Cage only protects in the case of low frequency E.M. waves. An EMP has such a fast rising time that it causes eddy currents in the wires of the Cage, driving the currents in the wires to the outside perimeter, increasing the effective resistance to such an amount that compensation of the fields is no more apparent, hence the EMP field will penetrate the Faraday Cage and still damage the equipment inside.
So what one needs is a massive metal enclosure, not a cage, and preferably made of gold, silver or copper, in decreasing order of preferability.
Then the thickness should be such that the surface penetration of the EMP is low enough at the inner side of the enclosure to prevent any damage to be done.
If one knows the characteristics of an EMP (I'm too lazy to look it up for now), such an enclosure can easily be designed.
However, it won't look like a Faraday Cage.
